In recent years, picture-taking equipments such as cameras have been popularized more and more and picture-taking opportunities in which silver halide photographic light sensitive materials are used have also been increased. In keeping with the above-mentioned circumstances, the silver halide photographic light sensitive materials have been strongly required to make their sensitivities and image qualities higher.
In addition to the above, there has been the tendency that more complicated and various characteristic improvements have been requested for the silver halide photographic light sensitive materials.
Particularly from the viewpoint for stabilizing the photographic characteristics, it has been demanded to improve the resistance to various pressures accidentally or inevitably applied to a silver halide photographic light sensitive material subject to photography, development and so forth.
As the means for improving the pressure resistance, there have so far been the means in which an iridium salt or a thallium salt is added to silver halide grains when the grains are formed. These means have been described in, for example, U.S. Pat. No. 2,628,167 and Japanese Patent Publication Open to Public Inspection (hereinafter referred to as JP OPI Publication) Nos. 50-116025/1975 and 51-107129/1976. However, these means have had such a problem that the sensitivity is lowered.
In addition to the above, JP OPI Publication No. 1-183644/1989 discloses a means of making use of a silver halide emulsion containing tabular-shaped silver halide grains having a silver halide phase containing silver iodide of 3 mol % or more and having a completely uniform silver iodide distribution of the silver halide containing the above-mentioned silver iodide. However this means has not been quite satisfactory to meet the requirements for further improving the pressure resistance.
Further, there have been the other known techniques in which the physical properties of a silver halide grain dispersing binder is changed by adding a plasticizer or other additives to a subject silver halide emulsion. For example, JP OPI Publication No. 2-135335/1990 discloses a technique in which a latex inherently comprising a methacrylate polymer having a glass transition temperature of lower than 50.degree. C. and an emulsion containing tabular-shaped silver halide grains are used. However, this technique cannot be said to be desired and the effects thereof cannot be satisfactory. Therefore, the more excellent developments of the techniques have been demanded.